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Posted

yo mofo's!!

i got a decent rattle on my topend when cold and warm, is it possible i could replace the rings or should i be looking at a piston kit and small end bairings??

sorry for the noob question i have never worked on a 2 stroke - plenty of 4 strokes!!

any advice on what to look for are welcome!

cheers

ken

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Posted

id probably have alook to see whats actualy making the rattle my self..

could just be barings.. could be one of the piston rings have gone and is now destroying the cylinder nicley for you....

id have a look.

2 strokes are really simple engines. they just like to be perfect, compared to a 4 stroke that is a bit more complicated to work on but dosent mind a few things being a bit iffy.

Posted

im hoping the barre lisnt knackered but if it is ill have to sort it out, bike is worth the money

to be honest its been doing it for 2 weeks now, been busy with work and baby so still using it every day hoping it wont die on me!!

do you think it could just be topend barings?

Posted

Pull the exhaust off and have a look in only takes a few min and you will have a better Idea as to what is going on.

If it's the top bearing and you keep running it..it will take the crank out with it in short order.

Posted

ahh man...

i hate it when things start going wrong - havent had it even 1 month grrrr

  • Moderator
Posted

best bet is to strip it down, check the bore, check the piston to bore clearance, check the rings end gap clearance, replace the small end bearing. You will no doubt find the specs in the manual

  • Moderator
Posted

yeh man i think ill buy the parts and do it over winter :(

I would be doing it now, cost nothing to get a set of gaskets, some circlips and a little end bearing.

The rattle could be rings, little end, even carbon on the piston crown.

It could be a cheap fix, just an hour or 2 and some scrubbing.

Leave it making an obvious rattle and it will die, simple as that. That is the biggest difference with strokers. When they are unhappy they die, fast! and normally expensively.

The little end could brake up, that will be bore, rings, crank etc. Piston slap? that could sieze at any time again crank etc at risk as well as yourself if on a fast road.

Could just be carbon causing hot spots on the piston needing a decoke.

Your bike is calling for help, listen.

Posted

its not calling louder than my bank though :(

ill have to park her up until i can get some cash together!!!

i have just paid £90 to rebuild my honda nsr jc20 forks that have been sent away about 3 months ago-unfortunatly i sold the bike a month ago so i have a set of forks rebuilt with heavyer oil for my weight with not bike to put them on..

so once i can get them sold on fleebay ill but that parts for topend rebuild - ill just throw in piston,rings,barings,gaskets and oil change while am at it.

ken

Posted

Thats a good idea to park it before something goes realy bad but,you should pull the top end off so you know if you need to bore it before you buy a piston

Posted

yeh, i think if i need to get it bored out i might look into a 150cc bore and piston...

ill crack the head next couple of days see whats going on!!

cheers lads very helpfull

ken

Posted

i know you can get the athena 170cc kit, i used to have it on my dt125re it was quick but it soon died on me lol

p.s how is everyone (airhead,Cynic sorry ive not been on for a while i've been buying and selling bikes to make some money :P)

Posted

150cc bore, can that be done without boring into the PV? Not to mention the 'L' plate situation!

as far as i know its possible as there is someone on ebay offering this service..

quick email to them and i shall find out

  • Moderator
Posted

and what comes next, suppose a ring breaks and scores the bore or something...just how many oversizes are left after you have it gouged out to 150cc?...If none then you'll just scrap the barrel hmmm

Posted

we can all sit here and talk about what ifs... who knows??

all i do is research things to find out if they are suitable for purchase, if i ask questions the seller cant answer then i wont go near it however i might stick with the 125 cylinder or i might look into the athena 170 topened.

if i open the topend up and find cylinder isnt damaged chances are i will replace piston/ring with small barings and save up for athena 170.

everything is not set in stone but i can see your point on the bore out, he is wanting near £400 for the service aswell which is about same price as athena kit was just thinking which of the two would be the better more reliable option over standard?

cheers

ken

Posted

yeh its expensive, this is from his listing

"

We are pleased to offer this excellent replacement 150cc GP Big Bore Kit

This is a 150CC GP Big Bore Kit

Its the most POWERFUL kit you can buy

Comes with a forged, single ring RACING PISTON, converted to flat top.

Also Includes your head remachined, Especially designed for the 150 Kit.

Barrel is Blue Printed, BORED and RE-PLATED.

Comes Complete with TOP END GASKET set and SMALL END BEARING.

You need to send your barrel to us for the work to be carred out"

ken

Posted

well if its blue-print it will have its ports tweaked and everything am i correct?

still think £400 is a lot though considering its a re-bore of your own cylinder, and not a pistion/gaskets/cylinder/head and barings. and even if it was i still think £400 was a bit much.

cant really see how a re bore tweak + piston would be much more than £250 personally. But i could just be being cheap again.

id probably "if i needed a rebore" just go up the 0.50 or or whatever the next available size is and get the piston/rings for that.

i dont think that would be any where near as expensive as 400.

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